Secondary memory configuration for data backup

Abstract

A data storage device includes a main storage memory and a non-volatile cache memory system. The non-volatile cache memory system comprises a master device, a first slave device communicatively coupled to the master device, the first slave device comprising a first non-volatile memory, and a second slave device communicatively coupled to the master device, the second slave device comprising a second non-volatile memory of a different type than the first non-volatile memory. The data storage device also includes a controller communicatively coupled to the main storage memory and to the non-volatile cache memory system, the controller is configured to, upon a power loss to the data storage device, store volatile data into the non-volatile cache memory system.

What is claimed is: 
     
       1. A data storage device, comprising:
 a main storage memory; 
 a non-volatile cache memory system comprising:
 a master device; 
 a first slave device communicatively coupled to the master device, the first slave device comprising a first non-volatile memory having a first performance level; and 
 a second slave device communicatively coupled to the master device, the second slave device comprising a second non-volatile memory of a different type than the first non-volatile memory, the second slave device having a second performance level that is higher than the first performance level, the first performance level and the second performance level each being a measure of a same performance aspect of the first slave device and the second slave device; 
 the first slave device and the second slave device sharing a signal from the master device, the master device configured to:
 prioritize the first slave device for data storage over the second slave device during normal operation of the data storage device, and 
 select the second slave device for data backup upon power loss to the data storage device; and 
 
 
 a controller communicatively coupled to the main storage memory and to the master device of the non-volatile cache memory system, the controller configured to, upon a power loss to the data storage device, store volatile data into the second slave device. 
 
     
     
       2. The data storage device of  claim 1 , and wherein the first non-volatile memory comprises a NOR serial Flash memory. 
     
     
       3. The data storage device of  claim 2 , and wherein the NOR serial Flash memory has a first data rate. 
     
     
       4. The data storage device of  claim 3 , and wherein the second non-volatile memory comprises a FeRAM non-volatile memory. 
     
     
       5. The data storage device of  claim 4 , and wherein the FeRAM non-volatile memory has a second data rate that is higher than the first data rate. 
     
     
       6. The data storage device of  claim 1 , and wherein the volatile data includes band write operation information. 
     
     
       7. The data storage device of  claim 1 , and wherein volatile data includes media cache link table information. 
     
     
       8. The data storage device of  claim 1 , and wherein the controller is further configured to employ the second slave device for data logging operations. 
     
     
       9. The data storage device of  claim 1 , and wherein the master device is a serial peripheral interface bus. 
     
     
       10. The data storage device of  claim 1 , and wherein the first slave device and second slave device receive a shared clock signal, signal output, and signal input from the master device. 
     
     
       11. The data storage device of  claim 1 , and wherein the master device generates a chip select signal for selecting the first slave device and a chip select signal for selecting the second slave device. 
     
     
       12. The data storage device of  claim 1 , wherein the main storage memory utilizes shingled magnetic recording technology. 
     
     
       13. The data storage device of  claim 1 , and wherein the performance aspect is a data storage rate. 
     
     
       14. A data storage device comprising:
 a non-volatile cache memory system; 
 a controller configured to:
 capture information from a volatile cache memory system during normal operation; 
 store the captured information into a first slave device of the non-volatile cache memory system during normal operation of the data storage device at a first data rate; and 
 upon a power loss from a system power to the data storage device, store volatile data into a second slave device of the non-volatile cache memory system at a second data rate that is higher than the first data rate. 
 
 
     
     
       15. The data storage device of  claim 14 , and wherein the first slave device comprises a NOR serial Flash memory. 
     
     
       16. The data storage device of  claim 14 , and wherein the second slave device comprises a FeRAM non-volatile memory. 
     
     
       17. A method comprising:
 providing a controller coupled to a main storage memory of a data storage device; 
 providing a first non-volatile memory as a first slave device having a first performance level to the controller; 
 providing a second non-volatile memory of a different type than the first non-volatile memory as a second slave device communicatively coupled to the controller, the second slave device having a second performance level that is higher than the first performance level, each of the first performance level and the second performance level being a measure of a same performance aspect of the first slave device and the second slave device, the first slave device and the second slave device sharing a signal from the controller; 
 prioritizing the first slave device over the second slave device for data storage by the controller during normal operation of the data storage device; 
 selecting the second slave device for data backup upon a power loss to the data storage device; 
 storing, by the controller, volatile data to the second slave device upon the power loss. 
 
     
     
       18. The method of  claim 17 , and wherein the first slave device comprises a NOR serial Flash memory. 
     
     
       19. The method of  claim 17 , and wherein the second slave device comprises a FeRAM non-volatile memory.